Understanding Europe’s sinking land starts below the surface

Land subsidence is the gradual sinking of the Earth’s surface. Its causes and impacts differ from one region to another, but the consequences can be significant: increased flood risk in coastal areas, damage to buildings and infrastructure, and reduced storage capacity in groundwater systems. The paper brings together lessons from decades of European research and shows how this knowledge can support risk assessments and decision-making.

Why does the land sink?

The study describes both natural and human-induced processes, including groundwater extraction, mining, drainage of peatlands, loading of soft soils, tectonic movement and geological adjustment after the last ice age. For policy and management, the human-induced causes are particularly relevant, because their effects can sometimes be reduced through different land or subsurface use, regulation or targeted monitoring.

The energy transition makes this knowledge more urgent. Geothermal energy, carbon capture and storage, underground gas storage and hydrogen storage all use the subsurface. Depending on local conditions and the specific application, these activities can cause or influence ground motion. Careful monitoring and integrated assessment therefore become increasingly important.

Satellites measure movement, not causes

Satellite radar has greatly improved the monitoring of ground motion. The Copernicus Land Monitoring Service, which includes the European Ground Motion Service, provides freely accessible information on ground motion across most of Europe. This makes it easier to identify subsiding areas and to compare patterns between countries.

But satellite data do not automatically explain why the ground is moving. To understand the underlying causes, measurements need to be combined with geology, groundwater levels, soil properties and information about human activities in the subsurface.

When land subsidence becomes noticeable

The impacts are already visible. In European coastal plains, the land is subsiding while sea levels are rising. This can increase damage to buildings, roads and critical infrastructure. Loss of groundwater storage capacity can also put water security under pressure. Climate change may intensify these risks, for example through drought, heatwaves and changes in groundwater recharge.

Better data, better decisions

Europe already has open data infrastructures, national monitoring programmes and collaboration between geological surveys, research institutes and policymakers. The next step is to connect these data more effectively. By combining satellite observations with subsurface data and physically based models, governments and companies can better interpret causes, assess risks and weigh possible measures.

This makes land subsidence not only a scientific issue, but also a matter of choices in groundwater use, energy production and land management. Better knowledge of the subsurface helps to underpin those choices for water, infrastructure, climate adaptation and the energy transition.